A Jones matrix OCT offers improved image stability, image quality, and depth range of image, wherein light from a wavelength-scanning light source is split into two optical paths, and a reference arm is provided along one optical path, while a probe arm that irradiates and reflects light onto the measuring target to generate object light is provided along the other optical path. The probe arm has a polarization delay unit that linearly polarizes the light and then splits it into S-wave component and P-wave component, where the S-wave component and P-wave component are superimposed through optical paths of different optical path lengths, respectively, after which optical detectors are used to detect different spectral interference beams in the depth direction of the measuring target corresponding to the vertically polarized component and horizontally polarized component, which respectively correspond to the S-wave component and P-wave component, to obtain four spectral interference signals.
